U.S. Pat. No. 4,067,884 assigned to Hoechst discloses perfluoroketones of formula (3): ##STR1## wherein R.sup.1 and R.sup.2 are independently perfluoroalkyl groups, which may contain at least one oxygen atom as an ether bond, R.sup.1 and R.sup.2, taken together, have 10 to 80 carbon atoms, and R.sup.1 and R.sup.2 may be linear, branched or cyclic. The perfluoroketones are neutral liquids which are stable against acids and oxidizing agents and useful as heat transfer media when they are of low molecular weight and as lubricants when they are of high molecular weight.
These perfluoroketones, however, have a boiling point as high as about 100.degree. to 500.degree. C. which limits their use. There is a need for perfluoroketones having a lower boiling point or unique properties so that they may find a wider variety of applications.